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#4 body mount reinforcement

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Old Dec 31, 2007 | 02:49 PM
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Default #4 body mount reinforcement

Both #4 body mount reinforcements on my '76 are rotted. The rest seem OK. If I loosen the #3 mounts a little, will I have enough room to remove the #4 cushion and replace the reinforcement? Also, is the reinforcement pop-riveted to the body? Finally, how is the cage and nut attached to the body?
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Old Dec 31, 2007 | 02:59 PM
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Originally Posted by billsfan
Both #4 body mount reinforcements on my '76 are rotted. The rest seem OK. If I loosen the #3 mounts a little, will I have enough room to remove the #4 cushion and replace the reinforcement? Also, is the reinforcement pop-riveted to the body? Finally, how is the cage and nut attached to the body?
Not sure about the loosening #3 as I had all body mounts out when I did mine.

The Cage nut is attached with 2 rivets before you put the new reinforcement on. For the reinforcement some use screws or bolts, some use rivets. I used rivets and everything came out fine. The hard one (Rivet) is the one in the back. You may need to drill a hole in the front of the rear wheel well to get put that rivet in.

Hope this helps.
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Old Dec 31, 2007 | 03:17 PM
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I did mine when the body was off. I used rivets on everything. I think you would be stressing the body panels,without removing all the body bolts.
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Old Dec 31, 2007 | 03:37 PM
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Since the reinforcement is held against thin fiberglass with small rivits or bolts, I used an extra step to strengthen mine. I filled the metal reinforcement with bonding adhesive before slipping it in place to bond everything together. You can then add rivits or bolt to finish things up. If your fiberglass is as chewed up as mine was, you need something to hold things together.

Just my comments. Ralph.
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Old Dec 31, 2007 | 03:58 PM
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I used a die grinder with a cutting wheel and cut the old reinforcement off. Used epoxy and screws to put them back on. Had to also cut the head off the body bolt and drove it up through the top, it took the cage nut out with it (2 rivets). I didnt use a new cage nut, just found a 7/16" nut and dropped the bolt thru from the top when I put it back and tightened it up. Put a lock nut on top of the other nut for added security. Mine is much stronger than it was originally.

Also, I would try and loosen all the body mounts some, if the rear is that bad you may want to go ahead and replace them all, it really wasnt that bad once I figured it out. Plenty of threads with pics on it here....
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Old Dec 31, 2007 | 06:48 PM
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Thanks everyone for the tips.
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Old Dec 31, 2007 | 08:37 PM
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I think you'll have to lift the body. You'll need at least 2-3 inches of clearance and simply loosening the other mounts won't allow enough clearance. Don't forget, the front end, forward the number ones, is nailed up pretty good.

Other than that, very good advice above,..and be glad it's not a convertible.
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Old Dec 31, 2007 | 10:48 PM
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I've got a few pics of this job on my Blog. All great advise above. I didn't bother with a new cage/nut assembly either, just used a large stainless washer and nut with a new grade 8 bolt. All the fiberglass under the reinforcement was broken on mine which I had to rebuild. I used OEM type rivets to secure the reinforcement bracket into place. The best rivets with the correct temper are from either Dr Rebuild or Paragon. The large 1/2" head pop rivets or bolts will work as well. I too applied adhesive to the bracket before installation. This fills in any voids between the bracket and body as well as secures it into place.

Good Luck with the project.
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Old Jan 1, 2008 | 12:51 AM
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Originally Posted by 73, Dark Blue 454
I think you'll have to lift the body. You'll need at least 2-3 inches of clearance and simply loosening the other mounts won't allow enough clearance. Don't forget, the front end, forward the number ones, is nailed up pretty good.

Other than that, very good advice above,..and be glad it's not a convertible.
and be glad it's not a convertible

Exaclty my question!

I have a 69 convertible and need to replace those cage nuts as the bolts snapped off when the body was taken off.

How do i get at them?

I am having allot of trouble even trying to get the hinges for the conv. top hatch off, might have to drilla hole in the back wheel well to access the outer upper bolts of the hinge.

Ideas
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Old Jan 1, 2008 | 10:55 AM
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I wrote quite a bit about the replacement process on my body mounts and #4 reinforcements this summer. Should be some helpful stuff in the archives under my name.
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